Cost-utility analysis of transcatheter aortic valve implantation versus surgery in severe aortic stenosis patients with intermediate surgical risk in Thailand.

BACKGROUND: Transcatheter Aortic Valve Implantation (TAVI) has been shown to provide comparable survival benefit and improvement in quality of life to surgical aortic valve replacement (SAVR) for treating patients with severe aortic stenosis (AS) at intermediate surgical risk. This study aimed to evaluate the cost-utility of TAVI compared with SAVR for severe aortic stenosis with intermediate surgical risk in Thailand.

METHODS: A two-part constructed model was used to analyze lifetime costs and quality-adjusted life-years (QALYs) from societal and healthcare perspectives. The study cohort comprised severe AS patients at intermediate surgical risk with an average age of 80 years. The landmark trials were used to populate the model in terms of mortality and adverse event rates. All cost-related data and quality of life were based on Thai population. Costs and QALYs were discounted at 3% annually and presented as 2021 values. Incremental cost-effectiveness ratios (ICERs) were calculated. Deterministic and probabilistic sensitivity analyses were conducted.

RESULTS: In comparison to SAVR, TAVI resulted in higher total cost (THB 1,717,132 [USD 52,415.51] vs . THB 893,524 [USD 27,274.84]) and higher QALYs (4.88 vs . 3.98) in a societal perspective. The estimated ICER was THB 906,937/QALY (USD 27,684.27/QALY). From a healthcare system perspective, TAVI also had higher total cost than SAVR (THB 1,573,751 [USD 48,038.79] vs. THB 726,342 [USD 22,171.63]) with similar QALYs gained to the societal perspective. The estimated ICER was THB 933,145/QALY (USD 933,145/QALY). TAVI was not cost-effective at the Thai willingness to pay (WTP) threshold of THB 160,000/QALY (USD 4,884/QALY). The results were sensitive to utility of either SAVR or TAVI treatment and cost of TAVI valve.

CONCLUSION: In patients with severe AS at intermediate surgical risk, TAVI is not a cost-effective strategy compared with SAVR at the WTP of THB 160,000/QALY (USD 4,884/QALY) from the perspectives of society and healthcare system.